May 2013: This Month in JoVE

Summary

Here are some highlights from the May 2013 Issue of Journal of Visualized Experiments (JoVE).

Protocol

Minimal Erythema Dose (MED) Testing

Carolyn J. Heckman¹, Rachel Chandler², Jacqueline D. Kloss³, Amy Benson², Deborah Rooney², Teja Munshi¹, Susan D. Darlow¹, Clifford Perlis⁴, Sharon L. Manne⁵, David W. Oslin²

¹Cancer Prevention and Control Program, Fox Chase Cancer Center, ²Department of Psychiatry, University of Pennsylvania, ³Department of Psychology, Drexel University, ⁴Department of Medicine, Fox Chase Cancer Canter, ⁵Cancer Prevention and Control Program, The Cancer Institute of New Jersey

This article describes how to conduct minimal erythema dose (MED) testing in order to determine the lowest dose of ultraviolet radiation that will cause erythema (burning) when administered to an individual.

Measuring Intracellular Ca²⁺ Changes in Human Sperm Using Four Techniques: Conventional Fluorometry, Stopped Flow Fluorometry, Flow Cytometry and Single Cell Imaging

Esperanza Mata-Martínez¹, Omar José¹, Paulina Torres-Rodríguez¹, Alejandra Solís-López¹, Ana A. Sánchez-Tusie¹, Yoloxochitl Sánchez-Guevara¹, Marcela B. Treviño², Claudia L. Treviño¹

¹Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología-Universidad Nacional Autónoma de México, ²Math and Sciences Department, Edison State College

Intracellular Ca²⁺ dynamics are very important in sperm physiology and Ca²⁺-sensitive fluorescent dyes constitute a versatile tool to study them. Population experiments (fluorometry and stopped flow fluorometry) and single cell experiments (flow cytometry and single cell imaging) are used to track spatio-temporal [Ca²⁺] changes in human sperm cells.

Air Filter Devices Including Nonwoven Meshes of Electrospun Recombinant Spider Silk Proteins

Gregor Lang, Stephan Jokisch, Thomas Scheibel

Biomaterials Research Group, University of Bayreuth

Spider silk fibers display extraordinary mechanical properties. Engineered Araneus diadematus Fibroin 4 (eADF4) can be processed into nonwoven meshes using electrospinning. Here, the eADF4 nonwoven meshes are used to improve the performance of air filtering devices.

Ex vivo Live Imaging of Single Cell Divisions in Mouse Neuroepithelium

Karolina Piotrowska-Nitsche^1,2, Tamara Caspary¹

¹Department of Human Genetics, Emory University School of Medicine, ²Department of Experimental Embryology, IGAB Polish Academy of Sciences

Here we develop the tools necessary for ex vivo live imaging to trace single cell divisions in the mouse E8.5 neuroepithelium

Quantitative Analysis of Autophagy using Advanced 3D Fluorescence Microscopy

Chun A. Changou¹, Deanna L. Wolfson², Balpreet Singh Ahluwalia³, Richard J. Bold⁴, Hsing-Jien Kung⁵, Frank Y.S. Chuang⁶

¹Department of Biochemistry and Molecular Medicine, NSF Center for Biophotonics Science & Technology, ²NSF Center for Biophotonics Science & Technology, University of California, Davis, ³NSF Center for Biophotonics Science & Technology, University of Tromsø, ⁴Department of Surgery, University of California, Davis, ⁵Department of Biological Chemistry, University of California, Davis, ⁶Department of Biochemistry and Molecular Medicine, University of California, Davis

Autophagy is a ubiquitous process that enables cells to degrade and recycle proteins and organelles. We apply advanced fluorescence microscopy to visualize and quantify the small, but essential, physical changes associated with the induction of autophagy, including the formation and distribution of autophagosomes and lysosomes, and their fusion into autolysosomes.